• Baltimore's Francis Scott Key Bridge collapsed after a container ship hit it.
• The bridge carries Interstate 695 across the Patapsco River, southeast of the Baltimore metropolitan area.
• Six people who may have fallen into the water after the crash are missing.

A major Baltimore bridge collapsed early Tuesday after it was hit by a large container ship.

Six people were missing after the collision at the Francis Scott Key Bridge, according to Paul Wiedefeld, Maryland's transportation secretary. Two people were rescued, with one transported to a trauma center in serious condition. The missing people may have fallen into the water.

Roland L. Butler Jr., superintendent for Maryland State Police, said at a press conference late Tuesday that the search and rescue effort was transitioning to a search and recovery mission. Butler said that divers would return to the site at 6 a.m.

Jeffrey Pritzker, the executive vice president of construction company Brawner Builders, told NBC News on Tuesday evening that the six workers are presumed dead. Pritzker said there was one survivor, but the company is not immediately releasing names.

The bridge carries Interstate 695 across the Patapsco River, southeast of the Baltimore metropolitan area.

The ship, the DALI, hit the bridge at around 1:30 a.m. ET,  when contractors were working on the bridge, according to Wiedefeld. The missing people are believed to be the construction crew who were repairing potholes on the bridge.

The ship's crew made a mayday call just before the crash which stopped cars from coming over the bridge, according to Maryland Gov. Wes Moore.

"These people are heroes," Moore said. "They saved lives."

Wiedefeld said that vessel traffic into and out of the Port of Baltimore is suspended until further notice.

"This is a very large incident, it involves a very large footprint," Baltimore City Fire Department Chief James W. Wallace said in a press briefing.

The National Transportation Safety Board is investigating the collapse and has a team of more than 20 people on the scene, according to NTSB Chair Jennifer Homendy. The agency is unable to verify the number and status of the crew aboard the ship or the number of casualties from the collision.

"The NTSB doesn't speculate. We provide facts, and so there isn't a lot we can share right now because the focus has been on the people," Homendy said at a Tuesday afternoon press conference.

When asked whether there were vehicles on the bridge when it collapsed, Moore said, "there is still an investigation going on."

Secretary of Transportation Pete Buttigieg said the Port of Baltimore does the most vehicle handling of all ports, which will have a "major and protracted" effect on supply chains.

"This is no ordinary bridge," he said at the press conference. "This is one of the cathedrals of American infrastructure. It has been part of the skyline of this region for longer than many of us have been alive. So the path to normalcy will not be easy. It will not be quick and it will not be inexpensive, but we will rebuild together."

Maryland officials and the FBI said there is no information to suggest the collapse was a result of terrorism.

"The preliminary investigation points to an accident," Moore said. "We haven't seen any credible evidence of a terrorist attack."

Completed in 1977, the bridge took the name of Francis Scott Key, whose poem was the foundation of the U.S. national anthem.

About 35,000 people use the bridge every day, according to Wiedefeld. Drivers in the area will have to use the far-busier Baltimore Harbor and Fort McHenry tunnels to cross the harbor for the foreseeable future.

Moore said the priority now is on search and rescue, but that the rebuilding of the bridge will be a long-term project.

"We are going to make sure that this is not just not just rebuilt, but that we are going to rebuild in a way that remembers the people who this tragedy has impacted," Moore said.

President Joe Biden said in remarks Tuesday afternoon he intends for the federal government to pay for the entire cost of rebuilding the bridge and that he expects Congress to support his effort.

"I've directed my team to move heaven and earth to reopen the port and rebuild the bridge as soon as humanly possible," Biden said.

Maersk confirms chartering vessel

The vessel that collided with the bridge was identified by the U.S. Coast Guard as a 948-ft Singapore-flagged container ship chartered by Maersk.

No Maersk crew or personnel were onboard the vessel, according to the company. Shipping data indicates that the vessel is under the management of Synergy Marine Group, which said in a statement that all 22 crew members on board, including two pilots, were accounted for.

"Whilst the exact cause of the incident is yet to be determined, the [ship] has now mobilised its Qualified Individual Incident response service," the group said. "The US Coast Guard and local officials have been notified, and the owners and managers are fully cooperating with Federal and State government agencies under an approved plan."

Marine traffic data suggests the ship was bound for Colombo, Sri Lanka.

MAJOR BALTIMORE TRAFFIC ALERT: AVOID I-695 southeast corridor. I-695 Key Bridge collapse due to ship strike. Active scene. Use I-95 or I-895. #baltraffic #mdtraffic

— MDTA (@TheMDTA) March 26, 2024

State of emergency

Emergency personnel remained on the scene after the bridge's collapse, according to the office of Maryland's governor.

"I have declared a State of Emergency here in Maryland and we are working with an interagency team to quickly deploy federal resources from the Biden Administration," Moore said.

"We will remain in close contact with federal, state, and local entities that are carrying out rescue efforts as we continue to assess and respond to this tragedy."

The Associated Press contributed reporting to this story.

Correction: This article has been updated to reflect that the Francis Scott Key Bridge carries Interstate 695 and crosses the Patapsco River.